Ultralow noise up-conversion detector and spectrometer at telecom band

TL;DR

This paper presents a highly sensitive upconversion single-photon detector and spectrometer operating at telecom wavelengths, achieving low noise and high efficiency for quantum communication applications.

Contribution

It introduces a novel upconversion detector with improved efficiency and noise performance, enabling advanced infrared spectrometry at telecom wavelengths.

Findings

Detection efficiency of ~30% achieved

Dark count rate at noise level of silicon APD

Spectrometer noise equivalent power of -142 dBm

Abstract

We demonstrate upconversion single-photon detection for the 1550-nm band using a PPLN waveguide, long-wavelength pump, and narrowband filtering using a volume Bragg grating. We achieve total-system detection efficiency of around 30% with noise at the dark-count level of a silicon APD. Based on the new detector, a single-pixel up-conversion infrared spectrometer with a noise equivalent power of -142 dBm was demonstrated, which was better than liquid nitrogen cooled InGaAs arrary.